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Vending Machine Energy Guide
Vending Machine
Energy Guide
Keep your refrigerated vending machine
from eating your change
They’re scattered throughout the United States in large cities,
suburban areas, and small, rural towns. They often stand
alone, but can sometimes be found in pairs and trios.
They are commonplace both indoors and outdoors at gas
stations, convenience stores, retailers, schools, parks, and
office buildings.
A total of more than 4 million refrigerated vending machines
dot the countryside, making them nearly as prevalent as the
well-known soft drinks they frequently sell.
Refrigerated vending machines represent a fertile ground for
potential energy savings.
Refrigerated Vending Machine Basics
• 90% of these machines are canned and bottled beverage units.
• Machines consume more than 12 billion kWh of electricity
per year.
• Site owners pay electric bills of $250 or more per unit per year.
• Machines have a 10 to 13 year life span.
• An estimated 250,000 new vending machines are sold each year.
(Source: Guide To Energy-Efficient Commercial Equipment, American Coucil for an
Energy-Efficient Economy)
Energy Consumption of Refrigerated Vending Machines
• In lab tests, the power demand increased by 20% and energy
consumption shot up 138% as the ambient temperature rose from
75°F to 130°F.
• Past research has shown that 800 to 1,000 kWh per year per new
vending machine could potentially be saved through adoption of
more energy-efficient technologies.
Vending Machine Components
A typical refrigerated vending machine is equipped with the
following components:
• Lights and ballasts
• Refrigeration system
coil
º Evaporator
Evaporator fan
º Accumulator
º Condenser coil
º Condenser fan
º Compressor
º Expansion device
º box and vending mechanisms
• Coin
Based on Southern California Edison (SCE) test results, the
compressor consumes the most power (Figure A).
FIGURE A
Refrigerated vending machines consume five times more
electricity than a typical home refrigerator.
• Energy consumption ranges from 7 to 16 kWh/day/machine
(2,500-5,690 kWh/year/machine).
(Source: Natural Resources Defense Council)
• Ambient conditions impact energy consumption. As
ambient temperatures rise, power demand and energy
consumption increase.
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Vending Machine Energy Guide
What Are the Effects of Ambient Conditions on Performance
of Refrigerated Beverage Vending Machines?
How can you help to reduce the energy usage of your
vending machine?
SCE’s Refrigeration and Thermal Test Center (RTTC) evaluated
the impact of five ambient conditions, ranging from 75°F and
45% relative humidity to 130°F and 15% relative humidity, on
the following performance parameters:
• Keep them in cool/shaded locations with least exposure to sun.
• Keep condenser coils clean.
• In low traffic areas, install an add-on controller to reduce the
power usage as a function of traffic.
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•
•
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We hope this information has been helpful and that
you’ll continue to explore the potential for making your
refrigerated vending machines more energy efficient. If
you’d like more information about improving your
equipment’s energy efficiency, contact:
Refrigeration load
Compressor power
Daily energy use
Energy efficiency
Product temperature
Frost on evaporator coil
Conclusions
Figure B below summarizes the effects of various ambient
conditions on the power and daily energy usage of a closedfront refrigerated beverage vending machine.
As the ambient conditions changed from 75°F and 45%
relative humidity to 115°F and 45% relative humidity:
• Impact on beverage temperature
maximum of 35°F increase in beverage temperature
º Afrom
the target 36°F setpoint
Maximum and minimum product temperature variance
º from 15°F to 39°F
• Impact on electric demand
Approximately 16% increase in electric power use
º
• Impact on customer’s electric bill
121% increase in daily energy use or
º Approximately
200 kWh for every 1°F ambient increase
• Southern California Edison
Refrigeration and Thermal Test Center
626-812-7660
www.sce.com/rttc
• Energy Star for Small Business
1-888-STAR-YES
www.energystar.gov
• Flex Your Power
www.flexyourpower.org
• California Energy Commission
1-800-555-7794
www.energy.ca.gov/efficiency/index.html
This Energy Guide is provided for your general information and is not intended as a
recommendation or endorsement of any particular product or company. Funding for
this Energy Guide is provided by California utility customers and administered by SCE
under the auspices of the California Public Utilities Commission.
• Impact on energy efficiency
26% decrease in total system
º Approximately
energy efficiency
FIGURE B – Vending Machine Power And Daily Energy Use at Various Ambient Conditions
2003-1204
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